Exercise-induced asthma and cardiovascular fitness in asthmatic children.

ABSTRACT

BACKGROUND: The role of physical training in the management of children with exercise-induced asthma is controversial. A study was undertaken to determine whether a relationship could be found between the occurrence of exercise-induced asthma and the degree of cardiovascular fitness in asthmatic children. METHODS: Twenty eight children aged 6-13 with mild to moderate asthma and dyspnoea during or after physical exercise were tested. All patients had a basal forced expiratory volume in one second (FEV1) of > 80% predicted. Twelve patients were taking corticosteroid maintenance medication by inhalation and 16 were not. Two exercise tests were performed on a treadmill to assess peak oxygen consumption rate (VO2max) and the percentage decrease in FEV1 after exercise. RESULTS: There was no correlation between the VO2max and the percentage decrease in FEV1. Patients not taking steroids showed a greater fall in FEV1 than those receiving corticosteroid medication (mean fall in FEV1 28.7% versus 6.6%). Four of the 12 children treated with steroids and two of the 16 children not taking steroids had a level of cardiovascular fitness lower than the 5th percentile for healthy Dutch children. CONCLUSION: Normal cardiovascular fitness does not prevent exercise-induced asthma.